Condensing gas water heater

ABSTRACT

A condensing gas water heating device includes a frame, a main heat exchanger and a condensing heat exchanger. The frame, main heat exchanger, and a condensing heat exchanger all are made of stainless steel. The main heat exchanger and the condensing heat exchanger are integrally welded with the flue of the frame along the flue gas flow path to form a heat exchanger assembly. A condensed water collector is arranged between the main heat exchanger and the condensing heat exchanger. By welding the frame, main heat exchanger and condensing heat exchanger, which are made of stainless steel, into the integrally structured heat exchanger assembly, the present invention simplifies the structure and processing technology of the heat exchanger assembly, saves the installation space and materials of the heat exchanger assembly, and improves the corrosion resistance of the heat exchanger assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Utility Patent Application No. 201210271497.1, filed Aug. 1, 2012, the contents of which of are incorporated herein by reference.

BACKGROUND

The present invention relates to a gas water heating device, in particular to a condensing gas water heating device.

At present, the typical heat exchanger of the condensing type gas water heating device in the prior art is two-segmented, which means that the heat exchanger mainly comprises a main heat exchanger and a condensing heat exchanger. Usually, the main heat exchanger is made of copper materials, while the condensing heat exchanger is made of stainless steel. The main heat exchanger and the condensing heat exchanger both consist of a heat exchange portion and a frame fixed on the periphery of the heat exchanger portion. The frames of the main heat exchanger and the condensing heat exchanger are connected together through parts such as flanges, screws, and clips. This connection structure is large in size and uses a plurality of parts and parts and materials vary with corrosion resistance. To prevent the condensed water from corroding some parts and causing leakage of the condensed water or corrosion to the whole heat exchanger assembly, the sealing performance of the connection structure is of great importance. For example, sealing materials resistant to a high temperature are adopted to avoid leakage of the condensed water. Therefore, the structure and processing technology of the existing heat exchanger assembly are relatively complicated.

Furthermore, the main heat exchanger adopted by the gas water heater in the prior art is usually made of copper and the material itself is corroded by the trace water solution of nitric oxide (NOx) which is condensed from the flue gas in the service process, so the performance of the main exchanger unit is greatly reduced, including a decline in thermal efficiency, excessive flue gas emission (primarily, the concentration of the carbon monoxide emission exceeds the standard) and perforation and water leakage of the heat exchanger. This can greatly shorten the service life of the heat exchanger.

SUMMARY

To solve the problems in the prior art, the present invention provides a condensing, gas water heating device, which simplifies the structure and processing technology of the heat exchanger assembly of the condensing gas water heating device and meanwhile improves the corrosion resistance and sealing property of the heat exchanger assembly.

The technical aim of the present invention is realized by the following technical solutions.

A condensing gas water heating device comprises a heat exchanger assembly including a frame, a main heat exchanger and a condensing heat exchanger. The frame, main heat exchanger, and condensing heat exchanger are all made of stainless steel and the main heat exchanger and the condensing heat exchanger are integrally welded with the flue of the frame along a flue gas flow path to form the heat exchanger assembly. Additionally, a condensed water collector is arranged between the main heat exchanger and the condensing heat exchanger.

The main heat exchanger and the condensing heat exchanger of the condensing gas water heating device provided by the present invention are both made of stainless steel and are welded to form an integrally structured heat exchanger assembly, thereby avoiding problems such as the complicated structure and processing technology of the heat exchanger assembly caused by adopting the connection structures such as flanges and screws which require a plurality of parts and high sealing performance. What is more, a condensed water collector is arranged between the main heat exchanger and the condensing heat exchanger, preventing the condensed water generated during the working of the condensing heat exchanger from damaging the heat exchanger assembly.

Furthermore, said condensed water collector is welded on the flue wall of the frame.

Furthermore, said main heat exchanger and condensing heat exchanger are both finned tube heat exchangers.

Furthermore, said flue of said frame is integrally formed of a metal material.

Furthermore, said metal material is stainless steel.

Furthermore, said main heat exchanger and condensing heat exchanger are brazed with the flue of the frame to form the heat exchanger assembly.

In a preferable scheme of the condensing gas water heating device provided by the present invention, the main heat exchanger and condensing heat exchanger of the heat exchanger assembly are both finned tube heat exchangers. The frame is made of an integral stainless steel material, which means that the heat exchanger assembly only uses one frame, while the main heat exchanger and the condensing heat exchanger are both arranged in the frame. After being assembled, the main heat exchanger, condensing heat exchanger and frame are brazed and molded into the heat exchanger assembly at one time. The heat exchanger assembly processed by this scheme is simple in structure and processing and small in size and is greatly improved in the aspects of sealing property and corrosion resistance.

Furthermore, the flue gas outlet end of said frame is provided with a flue gas collecting hood which is welded with the frame.

Furthermore, said flue gas collecting hood is made of stainless steel.

The flue gas collecting hood at the flue gas outlet of the heat exchanger assembly is integrally welded with the heat exchanger assembly, which simplifies the structure and process of the condensing, gas water heating device.

All in all, the main heat exchanger, condensing heat exchanger and frame of the condensing gas water heating device provided by the present invention is welded to form an integrally structured heat exchanger assembly which is simple in structure and processing and small in size and has greatly improved sealing property and corrosion resistance. Therefore the service life of the whole condensing, gas water heating device is prolonged, material and processing costs are saved, and remarkable economic benefits are created.

Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a heat exchanger assembly of a preferable condensing gas water heating device of the present invention.

FIG. 2 is a lateral view of a heat exchanger assembly of a preferable condensing gas water heating device of the present invention as shown in FIG. 1.

FIG. 3 is a lateral view of a heat exchanger assembly of a preferable condensing gas water heating device of the present invention as shown in FIG. 1 at an A-A position.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.

FIGS. 1-3 show the heat exchanger assembly of a condensing gas water heating device of the present invention. The heat exchanger assembly comprises a frame 1, a main heat exchanger 3 and a condensing heat exchanger 4 which are made of stainless steel and are arranged in a flue 2 of said frame 1 along the flue gas flow path; the frame 1 may be made of a metal material such as steel and the structure thereof is designed on the basis of actual application. The flue 2 is a barrel-shaped part, the lower end of which is coupled to a combustor 7 (FIG. 3) to suck flue gas inside. The upper end of the flue 2 is close to a flue gas outlet to exhaust the waste gas and the wall of the flue 2 is used for supporting and connecting the main heat exchanger 3 and the condensing heat exchanger 4. The main heat exchanger 3 and the condensing heat exchanger 4 are welded with the frame 1 to form an integrally structured heat exchanger assembly.

Said main heat exchanger 3 and the condensing heat exchanger 4 are both finned tube heat exchangers. The flue 2 of said frame 1 is integrally formed of a stainless steel material. The main heat exchanger 3 and the condensing heat exchanger 4 are integrally brazed with the flue 2 of the frame 1. Of course, in addition to brazing, the present invention can adopt other welding means well-known by those skilled in this field, such as fuse welding and pressure welding. The integral structure does not have connection points which tend to corrode and leak thus the process of preventing leakage of the condensed water by using the sealing material resistant to high temperature in the heat exchanger in the prior art is avoided. The cost, corrosion resistance and the overall sealing property of the gas water heater are greatly improved.

As shown in FIG. 3, the flue 2 of the present invention is also provided with a condensed water collecting plate 5 which is provided with an outlet and arranged between the main heat exchanger 3 and the condensing heat exchanger 4. In a preferable scheme of the present invention, said condensed water collecting plate 5 is welded on the flue wall, which is also provided with an outlet. This outlet is connected with the outlet of the condensed water collecting plate 5 and the corrosive condensed water collected by the condensed water collecting plate is discharged out of the gas water heater through the outlet.

The top of the flue 2 of the frame 1 in the present invention is also provided with a flue gas collecting hood 6. See FIGS. 1-3 for the flue gas collecting hood 6. The edge of the flue gas collecting hood 6 is adapted to the upper port of the flue 2 of the frame 1, and is preferably made of stainless steel and integrally welded with the heat exchanger assembly. The stainless steel can resist corrosion by the nitrogen oxides condensed from the flue gas and prolong the service life. Of course, the flue gas collecting hood 6 in the present invention can also be made from other anticorrosive materials well-known by those in this field. The stainless steel flue gas collecting hood is only a preferable scheme of the embodiment.

In conclusion, in the present invention, the main heat exchanger and the condensing heat exchanger are welded with the frame to form an integral structure, which simplifies the structure and processing technology of the gas water heater and avoids using a sealing material resistant to a high temperature in the gas water heater. What is more, the condensed water collecting plate is welded on the inner wall of the flue, thus effectively controlling the guide process of the condensed water. The condensing gas water heating device provided by the present invention is made of stainless steel materials, which effectively avoids the influences caused by the trace corrosive substances generated during the normal use of the main heat exchanger and therefore greatly improves the service life of the main heat exchanger. Thus, the main heat exchanger and condensing heat exchanger are consistent in the service life grade as the service life and safety of the whole condensing gas water heating device are improved. Additionally, costs in materials, processing and assembling are reduced and remarkable economic benefits are created.

The above embodiment is used for describing the present invention only and does not limit the present invention. Those already skilled in this technical field may make various changes within the spirit and scope of the present invention, therefore all equivalent technical schemes shall belong to the present invention. The patent protective scope of the present invention is limited by the claims.

Thus, the invention provides, among other things, a condensing gas water heater. Various features and advantages of the invention are set forth in the following claims. 

What is claimed is:
 1. A condensing gas water heater, comprising: a frame including a flue defining a flue gas flow path; a main heat exchanger integrally welded to the flue and disposed within the flue gas flow path; a condensing heat exchanger integrally welded to the flue and disposed within the flue gas flow path, where the flue, the main heat exchanger and the condensing heat exchanger define a unitary heat exchanger assembly; and a condensed water collector disposed within the flue between the main heat exchanger and the condensing heat exchanger.
 2. The condensing gas water heater of claim 1, wherein the condensed water collector is welded to the flue of the frame.
 3. The condensing gas water heater of claim 1, wherein the main heat exchanger and the condensing heat exchanger both are finned tube exchangers.
 4. The condensing gas water heater of claim 1, wherein the flue of the frame is formed of a metal.
 5. The condensing gas water heater of claim 4, wherein the metal is a stainless steel.
 6. The condensing gas water heater of claim 1, characterized in that the main heat exchanger and the condensing heat exchanger are brazed to the flue of the frame to form the heat exchanger assembly.
 7. The condensing gas water heater of claim 1, further comprising a flue gas collecting hood welded to a flue gas outlet end of the frame.
 8. The condensing gas water heater of claim 7, wherein the flue gas collecting hood is formed of stainless steel.
 9. The condensing gas water heater of claim 1, further comprising a combustor coupled to a lower end of the flue. 